The present invention relates to novel compounds having retinoid negative hormone and/or retinoid antagonist-like biological activities. More specifically, the invention relates to 4-aryl substituted benzopyran, 4-aryl substituted benzothiopyran, 4-aryl substituted 1,2-dihydroquinoline and 8-aryl substituted 5,6-dihydronaphthalene derivatives which may also be substituted by a substituted 3-oxo-1-propenyl group. These novel compounds have retinoid antagonist like-activity and are useful for treating or preventing retinoid and vitamin A and vitamin A precursor induced toxicity in mammals and as an adjunct to treatment of mammals with retinoids to prevent or ameliorate unwanted or undesired side effects. The invention further relates to the use of retinoid negative hormones for increasing the biological activities of other retinoids and steroid hormones and inhibiting the basal activity of unliganded retinoic acid receptors.
Compounds which have retinoid-like activity are well known in the art, and are described in numerous United States and other patents and in scientific publications. It is generally known and accepted in the art that retinoid-like activity is useful for treating mammals, including humans, in order to cure or alleviate the symptoms associated with numerous diseases and conditions.
Retinoids (vitamin A and its derivatives) are known to have broad activities, including effects on cell proliferation and differentiation, in a variety of biological systems. This activity has made retinoids useful in the treatment of a variety of diseases, including dermatological disorders and cancers. The prior art has developed a large number of chemical compounds which have retinoid-like biological activity, and voluminous patent and chemical literature exists describing such compounds. The relevant patent literature includes U.S. Pat. Nos. 4,980,369, 5,006,550, 5,015,658, 5,045,551, 5,089,509, 5,134,159, 5,162,546, 5,234,926, 5,248,777, 5,264,578, 5,272,156, 5,278,318, 5,324,744, 5,346,895, 5,346,915, 5,348,972, 5,348,975, 5,380,877, 5,399,561, 5,407,937, (assigned to the same assignee as the present application) and patents and publications cited therein, which particularly describe or relate to chroman, thiochroman and 1,2,3,4-tetrahydroquinoline derivatives which have retinoid-like biological activity. In addition, several applications are pending which are assigned to the assignee of the present application, and which are directed to further compounds having retinoid-like activity.
U.S. Pat. Nos. 4,740,519 (Shroot et al.), U.S. Pat. No. 4,826,969 (Maignan et al.) U.S. Pat. No. 4,326,055 (Loeliger et al.), U.S. Pat. No. 5,130,335 (Chandraratna et al.), U.S. Pat. No. 5,037,825 (Klaus et al.), U.S. Pat. No. 5,231,113 (Chandraratna et al.), U.S. Pat. No. 5,324,840 (Chandraratna), U.S. Pat. No. 5,344,959 (Chandraratna), U.S. Pat. No. 5,130,335 (Chandraratna et al.), Published European Patent Application Nos. 0 176 034 A (Wuest et al.), 0 350 846 A (Klaus et al.), 0 176 032 A (Frickel et al.), 0 176 033 A (Frickel et al.), 0 253 302 A (Klaus et al.), 0 303 915 A (Bryce et al.), UK Patent Application GB 2190378 A (Klaus et al.), German Patent Application Nos. DE 3715955 A1 (Klaus et al.), DE 3602473 A1 (Wuest et al., and the articles J. Amer. Acad. Derm. 15: 756-764 (1986) (Sporn et al.), Chem. Pharm. Bull. 33: 404-407 (1985) (Shudo et al.), J. Med Chem. 31: 2182-2192 (1988) (Kagechika et al.), Chemistry and Biology of Synthetic Retinoids CRC Press Inc. 1990 pp. 334-335, 354 (Dawson et al.), describe or relate to compounds which include a tetrahydronaphthyl moiety and have retinoid-like or related biological activity. U.S. Pat. No. 4,391,731 (Boller et al.) describes tetrahydronaphthalene derivatives which are useful in liquid crystal compositions.
An article by Kagechika et al. in J. Med. Chem 32:834 (1989) describe certain 6-(3-oxo-1-propenyl)-1,2,3,4-tetramethyl-1,2,3,4-tetrahydronaphthalene derivatives and related flavone compounds having retinoid-like activity. The articles by Shudo et al. in Chem. Pharm. Bull. 33:404 (1985) and by Jett et al. in Cancer Research 47:3523 (1987) describe or relate to further 3-oxo-1-propenyl derivatives (chalcone compounds) and their retinoid-like or related biological activity.
Unfortunately, compounds having retinoid-like activity (retinoids) also cause a number of undesired side effects at therapeutic dose levels, including headache, teratogenesis, mucocutaneous toxicity, musculoskeletal toxicity, dyslipidemias, skin irritation, headache and hepatotoxicity. These side effects limit the acceptability and utility of retinoids for treating disease.
It is now general knowledge in the art that two main types of retinoid receptors exist in mammals (and other organisms). The two main types or families of receptors are respectively designated as the RARs and RXRs. Within each type there are subtypes: in the RAR family the subtypes are designated RAR-xcex1, RAR-xcex2 and RAR-xcex3, in RXR the subtypes are: RXR-xcex1, RXR-xcex2 and RXR-xcex3. Both families of receptors are transcription factors that can be distinguished from each other based on their ligand binding specificities. All-trans-RA (ATRA) binds and activates a class of retinoic acid receptors (RARs) that includes RAR-xcex1, RAR-xcex2, and RAR-xcex3. A different ligand, 9-cis-RA (9C-RA), binds and activates both the RARs and members of the retinoid X receptor (RXR) family.
It has also been established in the art that the distribution of the two main retinoid receptor types, and of the several subtypes is not uniform in the various tissues and organs of mammalian organisms. Moreover, it is generally accepted in the art that many unwanted side effects of retinoids are mediated by one or more of the RAR receptor subtypes. Accordingly, among compounds having agonist-like activity at retinoid receptors, specificity or selectivity for one of the main types or families, and even specificity or selectivity for one or more subtypes within a family of receptors, is considered a desirable pharmacological property.
Relatively recently compounds have been developed in the art which bind to RAR receptors without triggering the response or responses that are triggered by agonists of the same receptors. The compounds or agents which bind to RAR receptors without triggering a xe2x80x9cretinoidxe2x80x9d response are thus capable of blocking (to lesser or greater extent) the activity of RAR agonists in biological assays and systems. More particularly, regarding the scientific and patent literature in this field, published PCT Application WO 94/14777 describes certain heterocyclic carboxylic acid derivatives which bind to RAR retinoid receptors and are said in the application to be useful for treatment of certain diseases or conditions, such as acne, psoriasis, rheumatoid arthritis and viral infections. A similar disclosure is made in the article by Yoshimura et al. J. Med. Chem. 38: 3163-3173 (1995). Kaneko et al. Med. Chem Res. 1:220-225 (1991); Apfel et al. Proc. Natl. Acad. Sci. USA 89: 7129-7133 Augusty 1992 Cell Biology; Eckhardt et al. Toxicology Letters 70:299-308 (1994); Keidel et al. Molecular and Cellular Biology 14:287-298 (1994); and Eyrolles et al. J. Med. Chem. 37: 1508-1517 (1994) describe compounds which have antagonist like activity at one or more of the RAR retinoid subtypes.
In addition to undesirable side-effects of therapy with retinoid compounds, there occurs occasionally a serious medical condition caused by vitamin A or vitamin A precursor overdose, resulting either from the excessive intake of vitamin supplements or the ingestion of liver of certain fish and animals that contain high levels of the vitamin. The chronic or acute toxicities observed with hypervitaminosis A syndrome include headache, skin peeling, bone toxicity, dyslipidemias, etc. In recent years, it has become apparent that the toxicities observed with vitamin A analogs, i.e., retinoids, essentially recapitulate those of hypervitaminosis A syndrome, suggesting a common biological cause, i.e., RAR activation. These toxicities are presently treated mainly by supportive measures and by abstaining from further exposure to the causative agent, whether it be liver, vitamin supplements, or retinoids. While some of the toxicities resolve with time, others (e.g., premature epiphyseal plate closure) are permanent.
Generally speaking, specific antidotes are the best treatment for poisoning by pharmacological agents, but only about two dozen chemicals or classes of chemicals out of thousands in existence have specific known antidotes. A specific antidote would clearly be of value in the treatment of hypervitaminosis A and retinoid toxicity. Indeed, as increasingly potent retinoids are used clinically, a specific antidote for retinoid poisoning could be life saving.
The present invention covers compounds of Formula I 
wherein
X is S, O, NRxe2x80x2 where Rxe2x80x2 is H or alkyl of 1 to 6 carbons, or X is [C(R1)2]n where R1 is independently H or alkyl of 1 to 6 carbons, and n is an integer between 0 and 2;
R2 is hydrogen, lower alkyl of 1 to 6 carbons, F, Cl, Br, I, CF3, fluoro substituted alkyl of 1 to 6 carbons, OH, SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons;
R3 is hydrogen, lower alkyl of 1 to 6 carbons or F;
m is an integer having the value of 0-3;
o is an integer having the value of 0-3;
Z is
xe2x80x94Cxe2x89xa1Cxe2x80x94,
xe2x80x94Nxe2x95x90Nxe2x80x94,
xe2x80x94Nxe2x95x90CR1xe2x80x94,
xe2x80x94CR1xe2x95x90N,
xe2x80x94(CR1xe2x95x90CR1)nxe2x80x94 where nxe2x80x2 is an integer having the value 0-5,
xe2x80x94COxe2x80x94NR1xe2x80x94,
xe2x80x94CSxe2x80x94NR1xe2x80x94,
xe2x80x94NR1xe2x80x94CO,
xe2x80x94NR1xe2x80x94CS,
xe2x80x94COOxe2x80x94,
xe2x80x94OCOxe2x80x94;
xe2x80x94CSOxe2x80x94;
xe2x80x94OCSxe2x80x94;
Y is a phenyl or naphthyl group, or heteroaryl selected from a group consisting of pyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl, imidazolyl and pyrrazolyl, said phenyl and heteroaryl groups being optionally substituted with one or two R2 groups, or
when Z is xe2x80x94(CR1xe2x95x90CR1)nxe2x80x94 and nxe2x80x2 is 3, 4 or 5 then Y represents a direct valence bond between said (CR2xe2x95x90CR2)n group and B;
A is (CH2)q where q is 0-5, lower branched chain alkyl having 3-6 carbons, cycloalkyl having 3-6 carbons, alkenyl having 2-6 carbons and 1 or 2 double bonds, alkynyl having 2-6 carbons and 1 or 2 triple bonds;
B is hydrogen, COOH or a pharmaceutically acceptable salt thereof, COOR8, CONR9R10, xe2x80x94CH2OH, CH2OR11, CH2OCOR11, CHO, CH(OR12)2, CHOR13O, xe2x80x94COR7, CR7(OR12)2, CR7OR13O, or tri-lower alkylsilyl, where R7 is an alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons, R8 is an alkyl group of 1 to 10 carbons or trimethylsilylalkyl where the alkyl group has 1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, or R8 is phenyl or lower alkylphenyl, R9 and R10 independently are hydrogen, an alkyl group of 1 to 10 carbons, or a cycloalkyl group of 5-10 carbons, or phenyl or lower alkylphenyl, R11 is lower alkyl, phenyl or lower alkylphenyl, R12 is lower alkyl, and R13 is divalent alkyl radical of 2-5 carbons, and
R14 is (R15)r-phenyl, (R15)4-naphthyl, or (R15)r-heteroaryl where the heteroaryl group has 1 to 3 heteroatoms selected from the group consisting of O, S and N, r is an integer having the values of 0-5, and
R15 is independently H, F, Cl, Br, I, NO2, N(R8)2, N(R8)COR8, NR8CON(R8)2, OH, OCOR8, OR8, CN, an alkyl group having 1 to 10 carbons, fluoro substituted alkyl group, having 1 to 10 carbons, an alkenyl group having 1 to 10 carbons and 1 to 3 double bonds, alkynyl group having 1 to 10 carbons and 1 to 3 triple bonds, or a trialkylsilyl or trialkylsilyloxy group where the alkyl groups independently have 1 to 6 carbons.
The present invention further covers compounds of Formula 101 
wherein
X is S, O, NRxe2x80x2 where Rxe2x80x2 is H or alkyl of 1 to 6 carbons, or X is [C(R1)2]n where R1 is independently H or alkyl of 1 to 6 carbons, and n is an integer between 0 and 2;
R2 is hydrogen, lower alkyl of 1 to 6 carbons, F, Cl, Br, I, CF3, fluoro substituted alkyl of 1 to 6 carbons, OH, SH, alkoxy of 1 to 6 carbons, or alkylthio of 1 to 6 carbons;
R3 is hydrogen, lower alkyl of 1 to 6 carbons or F;
m is an integer having the value of 0-3;
is o is an integer having the value of 0-3;
Y is a phenyl or naphthyl group, or heteroaryl selected from a group consisting of pyridyl, thienyl, furyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl, oxazolyl, imidazolyl and pyrrazolyl, said phenyl and heteroaryl groups being optionally substituted with one or two R2 groups;
A is (CH2)q where q is 0-5, lower branched chain alkyl having 3-6 carbons, cycloalkyl having 3-6 carbons, alkenyl having 2-6 carbons and 1 or 2 double bonds, alkynyl having 2-6 carbons and 1 or 2 triple bonds;
B is hydrogen, COOH or a pharmaceutically acceptable salt thereof, COOR8, CONR9R10, xe2x80x94CH2OH, CH2OR11, CH2OCOR11, CHO, CH(OR12)12, CHOR13O, xe2x80x94COR7, CR7(OR12)2, CR7OR13O, or tri-lower alkylsilyl, where R7 is an alkyl, cycloalkyl or alkenyl group containing 1 to 5 carbons, R8 is an alkyl group of 1 to 10 carbons or trimethylsilylalkyl where the alkyl group has 1 to 10 carbons, or a cycloalkyl group of 5 to 10 carbons, or R8 is phenyl or lower alkylphenyl, R8 and R10 independently are hydrogen, an alkyl group of 1 to 10 carbons, or a cycloalkyl group of 5-10 carbons, or phenyl or lower alkylphenyl, R11 is lower alkyl, phenyl or lower alkylphenyl, R12 is lower alkyl, and R13 is divalent alkyl radical of 2-5 carbons, and
R14 is (R15)r-phenyl, (R15)r-naphthyl, or (R15)r-heteroaryl where the heteroaryl group has 1 to 3 heteroatoms selected from the group consisting of O, S and N, r is an integer having the values of 0-5, and
R15 is independently H, F, Cl, Br, I, NO2, N(R8)2, N(R8)COR8, NR8CON(R8)2, OH, OCOR8, OR8, CN, an alkyl group having 1 to 10 carbons, fluoro substituted alkyl group having 1 to 10 carbons, an alkenyl group having 1 to 10 carbons and 1 to 3 double bonds, alkynyl group having 1 to 10 carbons and 1 to 3 triple bonds, or a trialkylsilyl or trialkylsilyloxy group where the alkyl groups independently have 1 to 6 carbons;
R16 is H, lower alkyl of 1 to 6 carbons;
R17 is H, lower alkyl of 1 to 6 carbons, OH or OCOR11, and
is zero or 1, with the proviso that when p is 1 then there is no R17 substituent group, and m is an integer between 0 and 2.
The compounds of the present invention are useful for preventing certain undesired side effects of retinoids which are administered for the treatment or prevention of certain diseases or conditions. For this purpose the compounds of the invention may be coadministered with retinoids. The compounds of the present invention are also useful in the treatment of acute or chronic toxicity resulting from overdose or poisoning by retinoid drugs or Vitamin A.
The present invention additionally relates to the use of RAR antagonists for blocking all or some RAR receptor sites in biological systems, including mammals, to prevent or diminish action of RAR agonists on said receptor sites. More particularly, the present invention relates to the use of RAR antagonists for (a) the prevention and (b) the treatment of retinoid (including vitamin A or vitamin A precursor) chronic or acute toxicity and side effects of retinoid therapy.
In one particular aspect of the present invention, there is provided a method of treating a pathological condition in a mammal. The conditions treated are associated with a retinoic acid receptor activity. This method involves administering to the mammal a retinoid antagonist or negative hormone capable of binding to one of the following retinoic acid receptor subtypes: RARxcex1, RARxcex2 and RARxcex3. The antagonist or negative hormone is administered in an amount pharmaceutically effective to provide a therapeutic benefit against the pathological condition in the mammal.
As an antidote to acute or chronic retinoid or vitamin A poisoning the RAR antagonist can be administered to a mammal enterally, i.e., intragastric intubation or food/water admixture, or parenterally, e.g., intraperitoneally, intramuscularly, subcutaneously, topically, etc. The only requirement for the route of administration is that it must allow delivery of the antagonist to the target tissue. The RAR antagonist can be formulated by itself or in combination with excipients. The RAR antagonist need not be in solution in the formulation, e.g., in the case of enteral use.
As an adjunct to therapy with retinoids and in order to prevent one or more side effects of the retinoid drug which is administered, the RAR antagonist can similarly be administered enterally or parenterally. The RAR antagonist and RAR agonist need not be administered by the same route of administration. The key is that sufficient quantities of the RAR antagonist be present continuously in the tissue of interest during exposure to the RAR agonist. For the prevention of retinoid toxicity, it is best that the RAR antagonist be administered concurrently or prior to treatment with the RAR agonist. In many situations the RAR antagonist will be administered by a different route than the agonist. For example undesirable skin effects of an enterally administered retinoid may be prevented or ameliorated by an RAR antagonist which is administered topically.
Another aspect of the present invention is a method of identifying retinoid negative hormones. The method includes the following steps: obtaining transfected cells containing a reporter gene transcriptionally responsive to binding of a recombinant retinoid receptor, the recombinant retinoid receptor having at least protein domains located C-terminal to a DNA binding domain of an intact retinoid receptor, measuring a basal level of reporter gene expression in untreated transfected cells, the untreated transfected cells being propagated in the absence of an added retinoid, treating the transfected cells with a retinoid compound to be tested for negative hormone activity, measuring a level of reporter gene expression in treated cells, comparing the levels of reporter gene expression measured in treated cells and untreated cells, and identifying as retinoid negative hormones those retinoid compounds producing a lower level of reporter gene expression in treated cells compared with the basal level of reporter gene expression measured in untreated cells. In certain preferred embodiments, of this method the intact receptor is an RAR-xcex1, RAR-xcex2 or RAR-xcex3 subtype. In other embodiments, the intact receptor is an RXR-xcex1, RXR-xcex2 or RXR-xcex3 subtype. The recombinant receptor can also be either a recombinant RAR or RXR receptor. In some embodiments, the recombinant receptor is a chimeric retinoid receptor having a constitutive transcription activator domain. Such a constitutive transcription activator domain can comprise a plurality of amino acids having a net negative charge or have an amino acid sequence of a viral transcription activator domain, such as the herpes simplex virus VP-16 transcription activator domain. In embodiments in which the constitutive transcription activator domain has a net negative charge, the retinoid receptor can be recombinant and have deleted therefrom a DNA binding domain, such as a DNA binding domain specific for a cis-regulatory element other than a retinoic acid responsive element. These elements include an estrogen responsive element. The transfected cell is preferably propagated in a growth medium substantially depleted of endogenous retinoids, such as one that includes activated charcoal-extracted serum. In this method, the reporter gene can be the luciferase gene, in which case, the measuring steps can involve luminometry. The reporter gene can also be the xcex2-galactosidase gene, in which case the measuring steps would involve a xcex2-galactosidase assay. The transfected cell can be a transfected mammalian cell, such as a Green monkey cell or a human cell.
Another aspect of the present invention is a method of potentiating a pharmacologic activity of a steroid superfamily receptor agonist administered to a mammal. This method involves coadministering to the mammal with the steroid superfamily receptor agonist a composition comprising a pharmaceutically effective dose of a retinoid negative hormone to potentiate the pharmacologic activity of the steroid superfamily receptor agonist. The pharmacologic activity is measurable in a reporter gene trans-activation assay in vitro, such as by measuring anti-AP-1 activity. The pharmacologic activity to be potentiated can be an antiproliferative activity, such as activity of the type measurable in retinal pigment epithelium. The steroid superfamily receptor agonist can be any of the following: a retinoid receptor agonist, a vitamin D receptor agonist, a glucocorticoid receptor agonist, a thyroid hormone receptor agonist, a peroxisome proliferator-activated receptor agonist or an estrogen receptor agonist. The retinoid receptor agonist can be an RAR agonist, such as all-trans-retinoic acid or 13-cis retinoic acid. The retinoid receptor agonist can also be an RXR agonist. A preferred vitamin D receptor agonist is 1,25-dihydroxyvitamnin D3. A preferred glucocorticoid receptor agonist is dexamethasone. A preferred thyroid hormone receptor agonist is 3,3xe2x80x2,5-triiodothyronine. The retinoid negative hormone is an RAR-specific retinoid negative hormone, which preferably has a dissociation constant less than or approximately equal to 30 nM. Example of the RAR-specific retinoid negative hormone include AGN 193109, AGN 193385, AGN 193389 and AGN 193871. The composition comprising a pharmaceutically effective dose of a retinoid negative hormone can be coadministered at the same time as the steroid superfamily agonist and be combined prior to coadministration. These can also be coadministered as separate compositions.